Ying Xu,Peng Chen,Lei Tang,Xiaojun Zhang,Feng Shi,Xuyang Ning,Jingli Bi,Yang Qu,Hongfei Liu
Most chemotherapy agents have serious side effects due to lack of tumor targeting, which affects their clinical application. In addition, as an essential characteristic of malignant tumor, hypoxia is attracting exclusive research focus regarding its non-invasive real-time tracing in novel targeting delivery system. Herein, we designed a mixed micelle with tumor targeting and hypoxia responsiveness for tumor therapy and imaging. In particular, the dual-modified mix micelles were self-assembled by folic acid (FA) and 2-(2-nitroimidazole) ethylamine (NI) conjugated polymers , in which paclitaxel (PTX) and quantum dots (QDs) were co-loaded into the hydrophobic core. The drug loaded micelles showed satisfactory drug encapsulation, good storage stability, and sustained release properties. In vitro cell experiments showed that the mixed micelles exhibited enhanced cytotoxic effect and improved the cellular uptake, especially under hypoxic conditions, which was due to the FA mediated active targeting effect and NI induced hypoxic responsive release. In vivo experiments further proved that the mixed micelles possessed outstanding tumor targeting and hypoxia responsive properties. Furthermore, the drug loaded micelles showed excellent anti-tumor effect and can realize real-time in vivo imaging. This work demonstrates that the dual-modified mixed micelles co-loading with PTX and QDs might provide a novel approach for tumor therapy and imaging.
Highly specific and effective cancer phototherapy remains as a great challenge. Herein, a smart nanoplatform (TENAB NP) sequentially responsive to light, low pH and hypoxia is demonstrated for multi-mode imaging guided synergistic cancer therapy with negligible skin phototoxicity . Upon 808-nm laser irradiation , TENAB NPs can generate hyperthermia to melt the phase change material (PCM-LASA) coat and thereafter release chemo-drug tirapazamine (TPZ). Meanwhile, under acidic pH, photosensitizer ENAB would turn “off” its charge-transfer state, generating prominent 1 O 2 for photodynamic therapy (PDT) and heat for photothermal therapy (PTT), respectively. Accompanied with PDT-induced hypoxia, the released TPZ can be activated into its cytotoxic form for tumor cells killing. Notably, owing to phase change material LASA coat and ENAB's pH sensitivity, TENAB NPs show negligible photosensitization to skin and normal tissues. As the multi-stimuli responsive mechanism, TENAB NPs demonstrate a promising future in cancer photo-chemo theranostics with excellent skin protection.